Psiberzerkerthere Just is barely 4X of Isp from classical rocket. too heavy payload must be delivered to fuel that propulsion. most sufficient way is, takeoff from ground with 1st stage of mp-ramjet, powered by thorium reactor; then we go onto VASIMIR or SPT-290, powered by SOPL; Moon landing & blastoff from there can be done with chemical propulsion 4 1st times. 4 2nd phase, we shall make there magnetic railways to take vehicles off with that. with 3rd phase, Moon Power Station must be created to power landing spacecrafts wirelessly.

most sufficient way is, takeoff from ground with 1st stage of mp-ramjet, powered by thorium reactor; then we go onto VASIMIR or SPT-290, powered by SOPL; Moon landing & blastoff from there can be done with chemical propulsion 4 1st times. 4 2nd phase, we shall make there magnetic railways to take vehicles off with that. with 3rd phase, Moon Power Station must be created to power landing spacecrafts wirelessly.

Ok, slow down. First of all, it's VASIMR, you keep adding an I, like it's some Russian name. Yes, a very impressive engine, for heavy interplanetary travel. Probably overkill for translunar.

Solar thermal has lower ISP, you're right, but it's practically free, and could be automated to figure 8 orbits in a sort of conveyor system, constantly transporting materials from lunar, to Earth orbit. SPT-290 is a hull effect ion thruster, which has a lower specific impulse than a theoretical thermal rocket. (Nuclear, or solar.)

SOPL, as you call it, or tether dynamic energy is fine when you're the space shuttle, and there's relatively little around. Right now, and for the past couple decades while the SST was flying, it had an orbit relatively uncluttered of sattelites, to trip on the cable. In the future, when the orbits get more, and more crowded, it will become less, and less practical to play out kilometers of tether down to lower orbits because everything up there is moving at kilometers/sec. You really can't maneuver likeat, either, because each change in moment affects the angle of the entire system. That turns your SOPL into a hazard for everything else in lower faster orbit, and that's just if you're the only one running one. If everyone does, your orbital system rapidly turns into a Kessler feild.

And finally, tether dynamics only work by moving through the Van Allen belts, which don't extend to the moon. If that's all you got for power, you'll have to carry a lot of batteries. Especially with the highest drain electromagnetic plasma thruster you could find. (VASMR.)

The Thorium Reactor you mention, that wouldn't happen to be the SSTAR, would it? The first S stands for "SMall", by the way, which for thermonuclear steam reactors means, about 15m (50') x 3m (10'), and massing hundreds of tonnes. That's just the power supply, never mind the cargo, life support, and engine, you'd need a Saturn 5 launch just to get that to orbit. And you're going to bootstrap this to the moon with Hall Effect thrusters?

_________________"You can't have everything, where would you put it?" -Steven Wright.

Last edited by Psiberzerker on Thu Feb 23, 2012 3:56 pm, edited 1 time in total.

This is a forum for discussion, and yes, arguing points. But if you can't remain civil, you will probably find no one to engage with here.

All right, I appologize. I annealed a bit from being told I'm wrong, and the only way to do it is a collection of mutually exclusive technologies. It's a pet peeve, but that's no excuse for hypocritcally insulting someone based on my own intelligence. I'll try to control myself.

_________________"You can't have everything, where would you put it?" -Steven Wright.

most sufficient way is, takeoff from ground with 1st stage of mp-ramjet, powered by thorium reactor; then we go onto VASIMIR or SPT-290, powered by SOPL; Moon landing & blastoff from there can be done with chemical propulsion 4 1st times. 4 2nd phase, we shall make there magnetic railways to take vehicles off with that. with 3rd phase, Moon Power Station must be created to power landing spacecrafts wirelessly.

Ok, let's apply some Scientific Method to this proposal, and see if I can help you with it? This means asking, and answering some questions.

1) is it possible? Yes, we could power a VASMR type engine with a SSTAR reactor. It'd actually be a pretty good fit, as far as the power scales, the reactor could handle the needs of the thruster. The hull effect thruster would be too small, unless you used a lot of them in a massive, and complex array, but they could be used to maneuver.

2) Is it practical. Ok, this thing is ginormus. The ractor alone is larger, and more massive than the 3 vehicles sent to the moon in the Appollo missions. (Conical capsule, LEM, and transfer stage, combined.) We don't have any Saturn IVs, we don't make them any more, nor do we have a booster with that capability, but we could make one.

This is a heavy freighter. I could see it working as a tug to get a lot of materials from the moon to Earth orbit with significant mining operations. I still think it would be better for an interplanetary mission, like manned exploration of Venus, or Mars, but if you really wanted to fill the Terra/lunar system with large habitats, this would be your vehicle.

SOPL will not work outside the Van Allen Belts. I don't think it's a good idea if you have crowded orbits either. Sorry. The rail launch can't be built large, and powerful enough to lift something the size of this freighter to Earth orbit. The atmospheric drag, and mass would require a gun hundreds of miles long, and have a muzzle velocity that would sound like a nutron bomb going off every launch. You wheren't clear though, if you ment to place it on the moon? There, a mass driver would have no atmosphere to fight, and about a sixth the gravity (or 1/36th the practical weight) to launch raw materials from the regolith to be picked up by your SSTAR/VASMR freighter.

_________________"You can't have everything, where would you put it?" -Steven Wright.

what do you get against SOPL? SOPL provides wireless transmission of Energy from Sun to orbital tugboats. Furthermore, it's scalable system & far cheaper than fuel depots onto orbits. 2nd moment, powerful thrust, we only need to take off from the ground, to jump from an one orbit to an another needs to've highest Isp's of possible ones 3rdly, SSTAR of the 1MW weighs around 5 tonnes.

I have been thinking about using a rail gun or maglev etc. to launch a system that exploits the plasma generated by the collision of a small cross section heat shield with the air. If you could pulse a em field you could both protect the craft by holding a envelope of plasma away from most of the craft you could both propel and cut drag like the russian rocket torpedo.

And you only need enough speed from the gun to initiate some higher efficiency engine like scram or this wake plasma drive idea. Not the energy for the whole trip, the more launch weight that can be chucked the better.

_________________Let not the bindings of society hold you back from improving it.... the masses follow where the bold explore.

Sigmamaglev on the Moon has great future because no Atmosphere out there & low gravity as well. railway has to've approx 50-100 km's of length to provide comfortable acceleration + not to lose too much power with heat.

Ok, SarKOY, i seem to have your SOPL confused with a magnetodynamic tether. Since I can't find any referance to it under that acronym on the internet, could you explicitely tell me what you're talking about? It stands for Solar Orbital Power Lines, am I right? but it's wireless?

_________________"You can't have everything, where would you put it?" -Steven Wright.

it's Just system of mirrors & collimators, deployed onto orbits, to concentrate Energy from the Sun to a chosen point of Space (4 example, solar panels of an orbital tugboat). Yep, angular velocity is problem out there.

Ah, ok. Could conceivably track with orbit, but would sure clutter things up in significant enough numbers. How many mirrors are we talking about here? I mean, all the ^v to launch them, + fuel to make them track to reflect light at the craft could just be put on the craft. Then you'd only have to worry about 1 thing to maneuver around. I'm all for not cluttering Earth orbit in the process of opening up routine affordable space travel. Traffic is murder at tens of miles per seccond.

Is it possible you could deploy this array in another place? Like the L1 solar-Earth libration point? The planet would only be in the way in a limited window, the rest of the time, it could be used to power interlunar trips. Probably an annular array, like a giant Fresnel lense with independant focusing mirrors, not unlike the aperture of the Chanda X-ray observatory sattelite. (A Wolter Telescope.)

_________________"You can't have everything, where would you put it?" -Steven Wright.

ideally there better to put'em as closer to Sun as possible. radiation at Earth got to be around 1366 W/m2. it would be great, if reflection could give 10-30% of received power. here we have some moments:

What I was talking about is a Convergent beam. In the relative vaccum around the Earth system, there wouldn't be significant scatter.

Quote:

it will be hella wise to R&D of a stuff to change reflection angle non-mechanically

By annular lenses, I mean rings, technically from Parabolic, and Hypebolic sections, nested in each other so the light is reflected in to the center ring, then foreward to a point ahead (towards the Earth/Moon. At that point, a mirror could be tilted to direct it, since the ship we're talking about is a moving target.

Hey, I'm trying to help with Your idea, here. Don't knock it!

_________________"You can't have everything, where would you put it?" -Steven Wright.

What I was talking about is a Convergent beam. In the relative vaccum around the Earth system, there wouldn't be significant scatter.

Amicus, ye're right of that, but i meant slightly another moment: incident rays have different angles that makes beam divergence + material of reflector absorbs some energy.

Quote:

By annular lenses, I mean rings, technically from Parabolic, and Hypebolic sections, nested in each other so the light is reflected in to the center ring, then foreward to a point ahead (towards the Earth/Moon. At that point, a mirror could be tilted to direct it, since the ship we're talking about is a moving target.